Adjustable wrap web guiding apparatus



Aug. 6, 1963 H. R. RICHARDS ET AL ADJUSTABLE WRAP WEB GUIDING APPARATUS 5 Sheets-Sheet l Filed Dec. 20, 1960 INVENTORS Howard R. Richards lex ander Vlexe N3 ATTORNEYS Aug. 6, 1963 H. R. RICHARDS ETAL 3,100,059

ADJUSTABLE WRAP WEB GUIDING APPARATUS 5 Sheets-Sheet 2 Filed Dec. 20, 1960 ATTORNEYS llg 6, 1963 H. R. RICHARDS ET AL 3,100,069

ADJUSTABLE WRAP WEB GUIDING APPARATUS Filed Dec. 20, 1960 5 Sheets-Sheet 5 `INVENTORS Howard RRic7zards ATTORNEYS Alexander BYg/ 3,100,069 ADJUSTABLE WRAP WEB GUING APPARATUS Howard R. Richards, Lakewood, and Alexander V. Alexei, Cleveland, Ghio, assignors to Industrial (Ivens, Incorporated, Cleveland, tllrio, a corporation or Ohio Filed Dec. 20, 1960, Ser. No. 77,641 Claims. (Cl. 226-17) This invention relates to apparatus for guiding and centering traveling vwebs of paper, fabric, tilm, metal and the like.

'Ihe invention involves the provision of a plurality of yadjustment factors in a compact web guiding apparatus. According to the invention, a plurality of rolls are provided which `are adapted lto skew :with respect to each other to varying degrees and simultaneously to adjust to difierent degrees of proiile interference. In this connection the present invention contemplates the particularly advantageous provision of such apparatus where the degree of prole interference at any given adjustment of the rolls varies across at least part of the extent of the web Width due, yfor example, to the skewing relationship between the rolls so that there is under most or all conditions a greater amount of wrap of the roll means and the web at the edge of the web than 4at points on the web located transversely inwardly from the edge.

Stated in other terms, according to the invention a plurality of rolls are provided, planar projections of which are adapted to adjust their angular spacing with respect to each other to vary-ing degrees and simultaneously to adjust to diierent degrees of interference. The projections of the rolls referred to here are those in a plane transverse to the path of -web travel. Such projections hereinafter be referred to a transverse-plane projections. In this respect the present invention contemplates the particularly advantageous provision of such apparatus where the degree of interference at any Igiven adjustment of the rolls varies across `at least a part of the extent of the web width due, for example, to the angular spacing between the transverse-plane projections of the rolls so that there is under most conditions a Igreater amount of wrap of the roll means `and the web at the edge of the web than at points on the web located transversely inwardly from the edge.

In one important aspect of the invention, the apparatus contemplated by the invention also may accomplish quickcorrect guiding action with respect to a passing web, in addition to the above features, by bodily shifting the several roll means together transversely with respect to the web.

Other advantageous automatic adjustments are contemplated by certain aspects of the invention, as disclosed below.

Examples of .the invention are illustrated in the accompanying drawings, in which:

FIGURE -l is a side elevation of web guiding apparatus embodying the invention as viewed along a direction d-irectly opposed to the direction of web travel and showin-g the apparatus in an intermediate position. Thus it will be understood that .the rolls as seen in FIGURE l are congruent with their transverse-plane projection.

FIGURE 2 is a plan view on a reduced scale showing the apparatus of FIGURE 1 together with like apparatus at the opposite side of the web.

FIGURE 3 is a side elevation taken line 3--3` in FIGURE 1.

FIGURE 4 is a view similar to a portion of FIGURE 1 with the mounting linkages being shown in diagrammatic form and with the apparatus shown in two limiting extreme conditions on either side of the intermediate condition illustrated in FIGURE 1.

vFIGURE 5 Ais a schematic illustration of one form of edge sensing means and associated control means for use from the plane of in connection with the web guiding apparatus contemplated by the invention.

FIGURE 6 is a plan view similar to FIGURE 2 showing another web guiding apparatus embodying the inventlon.

FIGURE 7 is a partly broken away elevation on a scale enlarged `from FIGURE `6 and taken from lines 7-7 in FIGURE 6.

FIGURE 8 is a sectional plan view of the central portion of the apparatus seen in FIGURE 7.

FIGURE 9 is a view of certain parts of the apparatus of FIGURE 7 in an alternative position.

FIGURE .101 is a fragment-ary sectional view taken from the planes of line Ill-10 in FIGURE 7.

As shown in the drawings, there are provided iirst roll means comprising a single roll 10 and second roll means comprising a pair of rolls I11 `and 12. The rolls 11 and 12. move with each other. The several rolls are in guiding relationship with respect to a passing web 16 which is moving in the direction indicated by the arrows in FIG- URE 2. The roll `l1 of the pair of rolls 11 and 1?. which comprise the second troll means is located on the approach side of the single roll 10; and the roll '12 of the pair of rolls 11 'and 12 which comprise the second roll means is located on the withdrawal side of the single roll 10.

Although in the particular invention described the second roll means comprises the pair `of rolls 11 and 12, some aspects of the invention contemplate the provision of only a single roll. In this connection one of the roll means 11 for 12 could be eliminated and many of the features and advantages of the present invention would nevertheless obtain.

Each of the rolls l0-'12 is cantilevered from a mounting -means to be described below, and each of the rolls 10- 12 extend from such mounting means partially across the transverse extent of the passing web :13 as most clearly shown in FIGURE 2. Each of the rolls 1(l-12 is journaledon its `own cantilevered shaft 20-22 by inboard journal means 2 5 and outboard journal means 26.

If desired, the roll assemblies may not have such an attitude that they are perpendicular or normal to the path of rtravel of the |web as actually shown in FIGURE 2, but rather may be somewhat canted, that is, angularly displaced from a normal-to-web-path attitude. They should be canted in such a rotational direction that the inboard ends or free ends of the rolls 10-41-2 are furthest downstream with reference to the direction of web travel, that is, Vas viewed in yFIGURE 2, the inboard or free ends of the rolls 10-12 would be closest to the lower margin of the drawing. T-his degree of cant may be adjusted by -bolting the base frame shown in FIGURE 1 at diierent angular positions with respect to a vertical axis.

The shaft 20 is pivotally `ailixed to and supported on the doubled lever arms 30 and 40. Similarly the shaft 21 is pivotally .atiixed to and supported on the doubled lever yarms 31 and 41, .and the shaft 22 is pivotally affixed to and supported on the doubled lever arms 32 and 42. The doubled lever arms 30--32 and 40-42 are respectively supported on the upstanding brackets Sil- 52. and 60-62. The top ends ofthe levers 31 and 32 are joined by a shaft 3S (FIGURE 3). A pair of links 36 extend from the upper end of the doubled lever 30 to the shaft 35- so that shifting of the pivot connections 37 (FIGURES '1 and 3) between the upper end of the lever 30* and the links 36 causes shifting of the shaft 3S and actuation of the levers 31 and 32 pivoted thereto. The centr-al element of the pivot connection 37 is the stem of a yoke 34 (FIGURE 2) The forked end of the yoke `2idis pivoted to a trunnion bar 38 which is engaged by a threaded shaft 39 powered by a reversible air motor 46.

The several doubled levers land similar elements, such as-the links 36, include'suitable cross bars 48 (FIG- URI-3.1).

Y The apparatus located on the opposite side of the web 1-3 is virtually a duplicate of the apparatus described above with the correspondingly numbered elements being arranged symmetrical relationship -with respect to the in- Provided in the vicinity of the guiding apparatus at eachH side of they web is la senser unit operatively associated with the guiding apparatus at the same side of the web fthroughthe control means (including the motor 46) schematically illustrated in FIGURE 5. Many components of such-control'means may be positioned within the hous- I ing 54 illustrated in FIGURE 2. The edge sensing unit y"may comprise a tubev 55 having a slot 56 and supplied ywith"'low-pressure air through a spring-loaded regulator 57 which reduces the pressure of' air supplied in the line 58 to say about 5 psi.

5 5 is imposed on the input side' of a pressure multiplier 5=9 throughline 64. Y Operating air is supplied by the pres- 5 sure' multiplier throughline 65` from the air supply line 518 ata suit-able pressure of say 30 p.s.i. established by the spring-loaded pressure regulator 66. The output line 67 varies in'pressure in, a well known manner according to The static pressure on the tube the input pressure signal through line l64 to thereby actuate the diaphragm 68 of diaphragm-actuated spring-loaded valve 69' t'o'port air from the air supplyv line 58 and springloaded pressure regulator -to the air motor 46 through fj rlines 71 and 72 for for-ward, zero land reverse rotation "thereof Vaccording to the position of the edge of the web 13 overethe slot 56. -Other edge sensing and web control means may be employed and may comprise mechanical,

pneumatic,` hydraulic, or electronic means or combinantionsthereof, a number of Variations of such senser and control means being known to the `art.

l It will be'seen from the figures that the web 13, traveln' 'ing lalong its :given direction, extends under theroll means and over the roll means 111 and '12 and that't'he degree Y of interference between the web engaging profiles of these rolls as viewed along the direction of web travel or along ,a direction directly opposed to the direct-ion of web travel (the direction of view in FIGURE 41 being the latter) determines the degree of wrap of .the web on the rolls.

Iny the particular 'apparatus illustrated, the web engaging profiles ofthe rolls 1v1 and '12 `are exactly in alignment and j therefore in FIGURES 1 and 4, only the nearest profile,

that ofthe roll yi12, is labeled (with the reference character 12a). The relevant profile of the roll 10 is labeled 10a.

'Stated another way, -the "degree of interference between the transverse-plane projections of the rolls'determines the degree of wr-ap :of vthe weh on the rolls.

It will be seen from FIGURES 1' and 3 that the roll i '1" mounting means comprising the linkages describedabove is such afs to progressive-ly adjust the profile relationship ,of-the first roll" means (the-roll 10) on the one hand and ,the second roll'means (the rolls 111 and 12) on the other hand relative to each other back `and forth between a Afirst Y v'condition illustrated in dotted lines in FIGURE 4 Where therelar'e relatively low'degrees of (l) skewing and (2) profile interference'between the first and second roll means and Ta "second condition illustrated in solidV lines in FIG- URE 4Awhere 'there are relatively high degrees of (1) In the particular ,secondroll means (the rolls 11 and 12) on the other hand. The degree of -skewing and profile interference at the V.intermediate position illustrated in FIGURE l will be seen to be intermediate that of the rst'a-nd second limit- 4 ing end conditions shown in FIGURE 4. The change in skewing and profile interference is progressive as the rolls are moved from the first limiting end condition to the second limiting end condition.

Stated in other terms, it -will be seen that the described linkages are such as to adjust the relationships of the first and second noll means relative -to each other back and -forth between a. first'condition illustrated in dotted lines in FIGURE 4 -where there are relatively low degrees of |(l) angular spacing Iand (2) interference between the transverse-plane projections of the first and second roll lmeans 4and -a `second condition illustrated in solid line in FIGURE 4 where there are relatively high degrees of (l) angular `spacing and (2) interference between thetransverse-plane projections of the first and second roll means. In the particular apparatus illustrated, the degree of -angul-ar spacing between the transverse-plane projections of lthe first and second roll means illustrated in dotted lines i-n FIGURE 4 is zero. The degree of Vinterference between the transverse-plane projections of lthe first and second roll means is also zero.

The degree of angular spacing lof the transverse-plane projections ofthe first and second roll means and the degree of interference between the vtransverse-plane projections of the first and second roll means at the intermediate position illustrated in xFIGURE l will be seen to be intermediate that of the first 'and second limiting end conditions shown in FIGURE 4. The change in the degree of angular spacing and the degree of interference is progressive as the rolls are moved from the first limiting end 'condition to the second limiting end condition.

It is particularly to lbe noted that in the illustrated apparatus, the linkages comprising the roll mounting means are 'such as -t-o shift the roll 10 on the one hand and the rolls 11 and .12 on the other hand back and forth together transverse to the direction of -web travel incident to the l. of the shaft 22) on the other hand as shown in FIG- URE 4. It will be understood that the axis of the roll 11 and the shaft 21 would in the diagrammatic showing of FIGURE 4 remain located immediately behind the axis 12b.

It will be seen that the rolls '10, 1.1 and 12 are cantilevered on the linkages comprising the mounting means for the several rolls so as to extend from such mountving means partially across the transverse extent of the web. Thus the free ends of the rolls 10-12 are spaced out disassembly of the apparatus or emptying of the web processing line'onwhich the apparatus is used.

In the illustrated apparatus the roll assemblies at the opposite sides of the web as shown in FIGURE 2 operate independently of each other, each operating in respouse to the sensed position of the associated edge of the web -13\.

In one aspect, the invention contemplates automatic change ofthe degree of cant incident to movement of the rolls back' and forth between the above-mentioned rst and second' conditions so that at the first condition of `low degrees of skewing and prole interference, there is also a 'low degree of canting, and at the second condition kof high degrees of skewing and'prole interference, there is also a high degree of canting.

' To this end there may be provided the apparatus shown in FIGURES 6 1() for guiding a web L13, including lrolls 110, t111,`1\12; shafts`120, 121, 122; lever arms 130,

'131, 132, 140, 141, l142; reversibleV air motors `146, brackets V150, 151, '152, 160, 161, 162, and edge sensing elements 154, all corresponding in structure and function to those elements of FIGURES :l-S which are numbered with the same last two digits.

The brackets 150, 151, 152, 160, 161, y162 are carried on a base frame 175 which is similar in shape to the stationary frame shown in FIGURES 1 3. However the frame 175 is pivotally associated with a stationary pivot bolt 176 and carries depending wheels 177 which are guided in arcuate tracks 178.

r[he lever arm 132 is pivotally mounted to the bracket 152 by means of a shaft 179 (see FIGURE 10) to which the lever arm 132 is keyed. Also keyed to the shaft 179 is a lever 180. The lever 180 is linked by a pinand-slot connection to one end of a link 181. The opposite end of the link 181 is restrained against anything other than angular movement by a ball-and-socket connection to a fixed point.

The result is that as the apparatus of FIGURES 6-10 moves back and forth between a first condition of low degrees of skewing and profile interference and a second condition of high degrees of skewing and profile interference, it also moves respectively back and forth between a relatively low degree of angular displacement from normal-to-web-path attitude (say 35) to a relatively high degree of such angular displacement (say l0-l8), as illustrated in FIGURE 6. As will be clear from FIGURE 6 the term normal as used in the expression normal-to-web-path attitude has reference to a relationship of perpendicularity to the centerline of the traveling web or, equivalently, a relationship of perpendicularity to any line or plane parallel to such centerline of the traveling web.

This invention is not restricted to the slavish imitation of each and every one of the details described above which have been set forth merely by way of example with the intent of most clearly setting forth the teaching of the invention. Obviously, devices may be provided which change, eliminate or add certain specific structural details without departing from the invention. For example within some of the broader aspects of the invention, the roll '11 could be eliminated, the roll 12 could be tied to a stationary mounting so that it would permanently remain at the position shown in dotted lines in FIGURE 4, and the roll 10 could be mounted for angular movement only between the dotted line position shown in FIGURE 4 and a second position similar to the angularly disposed solid line position of the roll 10 as actually shown in FIGURE 4 but directly overlying the stationary roll 12. 'Ihe roll 10 would be moved between these two positions by the motor 46.

What is claimed is:

l. Web guiding apparatus comprising first and second roll means for guidingly engaging a web traveling along a given direction and extending under one of said first and second roll means and over the other whereby the degree of interference between the Web engaging profiles of said first and second roll means as viewed along said direction of web travel determines the degree of wrap of said web thereon, roll mounting means for angularly shifting both said first and second roll means to thereby progressively adjust the profile relationship of said rst and second roll means relative to each other back and forth between a first condition where, as between said first and second roll means, there are relatively low degrees of (l) skewing and (2) profile interference and a second condition Where, as between said first and second roll means, there are relatively high degrees of (l) skewing and (2) profile interference.

2. Web guiding apparatus comprising first and second roll means for guidingly engaging a web traveling along a given direction and extending under one of said first and second roll means and over the other whereby the degree of interference between the web engaging profiles of said first and second roll means as viewed along said direction of web travel determines the degree of wrap of said web thereon, roll mounting means for angularly shifting both said first and saidvsecond roll means to thereby progressively adjust the profile relationship of said first and second roll means relative to each other back and forth between a first condition where, as between said first and second roll means, there are relatively low degrees of (l) skewing and (2) profile interference and a second condition where, as between said first and second roll means, there are relatively high degrees of (l) skewing and (2) profile interference with the degree of profile interference between said rolls at said first condition being zero.

3. Web guiding apparatus comprising first and second roll mea-ns for guidingly engaging 1a web traveling along a given direction 'and extending under one of said first and second roll means and over the other whereby the degree of interference between the web engaging proles of said first and second roll means as viewed along said direction of fweb travel determines the degree of wrap of said web thereon, roll mounting means to progressively adjust the profile relationship of sai-d first and `second roll means relative to each other back `and forth between a first condition where, as between said `first and second roll means, there are relatively low degrees of (il) skewing and (2) profile interference land -a second condition where, `as between said first and second roll means, there are relatively high degrees of (il) skewing and (2) profile interference, lsaid roll mounting means including means to Shift Said first and second roll means back and forth together transverse to the :direction of web travel incident to said progressive adjustment back .and forth between said first )and second conditions.

4. Web guiding apparatus comprising first and second roll means for guidingly engaging -a web traveling along a given direction and extending under one of said first and second roll means and over the other whereby the degree of interference between the web engaging profiles of said first 'and second roll means as viewed along said direction of web travel determines the degree of wrap fof said web thereon, roll mounting means for angularly shifting both said first and said second roll means to thereby progressively adjust the profile relationship of said first and second roll means relative to each other back and forth between a first condition where, as between said first and second roll means, there -are relatively low degrees of (il) skewing and (2) profile interference and a second condition where, yas between said first and second roll means, there are relatively high degrees of (l) skewing and (2) profile interference, one of said first and second roll means comprising a single roll and the other lof said first and second roll means comprising a pair of rolls one of which is located on the approach side of said single roll 'and the other of which is located on the withdrawal side of said single roll.

5. Web guiding apparatus comprising lfirst yand second roll means for gudingly engaging a web traveling along a given direction and extending under one of said first and second roll means and over the other whereby the degree of interference between the web engaging profiles of said lfirst and second roll means as viewed along said direction of web travel determines the degree -of wrap of said web thereon, roll mounting means for angularly shifting both said first 'and said second `roll means to thereby progressively adjust the profile relationship of said first and second roll means relative to each other back and fourth between a first condition where, as between said first and second roll means, there are relatively low degrees of (1) skewing and (2) profile interference yand a second condition where, as between said first and second roll means, there are relatively high degrees of (1) skewing and (2) profile interference, each of -said first and second roll means comprising at least one roll cantilevered from :said mounting means to extend therefrom partially racross the transverse extent of 4said web.

6. Web guiding apparatus comprising first and second roll means vfor guidingly engaging a web traveling along forth between a first condition where, as lbetween said first and second-rollmeans, there are relatively low degrees of (1) skewing and Y(2) prole interference and a second Vcondition where, as between Alsaid -iirst andrsecond roll means, there are relatively high degrees of (1) skewing f and (2) preme-interference, one of said rst and seco-nd roll means comprising a single roll and the other of `said iirst and second roll means comprising a pair of `rolls one of which is located on the approach side of said single roll j and the other of which is located on the Withdrawal side of said single roll, each of said tirstand second roll means comprising at least one roll cantilevered from'said mount- `ingV means -to extend therefrom partially acnoss the trans- :verse extentl of said web.

7. Web guiding |apparatus comprising first and second roll means vfor guidingly engaging av web traveling along a given direction and extending under one of said iirst and second roll means and over the other whereby the degree of interference betweenthe web engaging profiles of said clirst and second rollmeans as viewed along said direction of web travel determines Athe degree of Wrap of said web thereon, roll mounting means to progressively adjust the prole relationship of said lirst and second roll means relative to each other `back :and forth between a first condition where, as between` said iirst and second roll means, there are relatively low degrees of (l) skewing -and (2) profile interference and a secondy condition where, as

between said iirst end secondroll means, `there are' rela- I tively. high degrees of (1) skewing and (2) proiile interference, said roll mounting meansincluding meansfor respectively increasing and decreasing the degree of angular displacement of saidirst and second roll' means for a normal-to-zweb-path attitude asisaid rolls move back and forth between said iirst and second-conditions.

8. Web guiding apparatus comprisingfirst and second roll vmeans for 'guidingly engaging la web traveling lalong a given direction and extending over one ofsaidrst and `second roll means and under the other Whereby'the Vdegree of interference between the transverse-plane projections of said rst and second roll means determines-the degree of Wrapofthe web thereon, roll mountingmeansv for angularly shifting both said first and saidsecond Aroll means to thereby progressively 'adjust the relationships of the transverse-plane projections of said' tirst and second degrees of (1) angular spacing and (2) interference between the transverse-plane projections of the first. and

' second roll meansand -a second condition where there are relatively high degrees of (l) angular spacing and (2) interference between thetransverse plane projections of the'rst and second roll means. Q "Web guiding' apparatus comprising first and second Aroll'mean-s ifor Kguidingly engaging a web traveling Ialong a given direction and extending over one of said iirst 4and second roll means and underthe other whereby the degree of interference between the transverse-plane projections of said rst and second'roll means determines the degree of Wrap of the web thereon'roll mounting means to progressively-adjust the relationships of the transverse-plane projection-s of said first and second roll means with respect to each Votherback and forth between la ir-st condition where Vthere are relatively low degrees of (l) angular spacing and (2) interference between the transverse-plane projections of the first and second roll means and a second condition where thereiiare relatively high degrees of (l) angular spacing andr (2) interference between the 4transverse-plane projections of the first rand second roll means,

said roll mounting means including means to shift said iirst and second roll means back and -forth together transverse tothe direction of web travel incident to said progressive' adjustment back and forth between said rst and second conditions.

10.' Web guidi-ng apparatus comprising rst fand second roll means for guidingly engaging a webl traveling along a given direction land extending over one of said iirst and second roll means and under the other whereby the degree of interference between the transverse-plane projections of-said rst rand-second roll'means determines the degree of wrap of the web thereon, noll mounting means to progressively adjust the 'relationships of the transvserse-plane projections of said iirst and second roll means with respect to' eachother-back :and forth between a -irst condition Wherethere are relatively low degrees of (l) angular spacing Iand (2).` interference between the transverse-plane projections of the rst and second Iroll means Vand asecond condition where there arerelatively high degrees of (l) angular spacing and (2) interference between-the transverse-plane projections of the nrst `and secondi-011 means,

said -rollrnounting means including means for respectively increasing and decreasing the degree of angular displacement ofsaidiirst and second vroll means from ya normalto-webpath attitude as said rolls move back and forth `vbetween said first andseeond conditions.

` roll means with respect to each other back-and forth bei `tween a iirst conditionwhere `there are relatively-lo|w -References'Cited in the iile of this patent I UNITED STATES PATENTS ,-1,`54l,'190 r Smith June 9, 1925 .12,476,070 Solliday July 12, 1949 ,L 2,639,483 Wester May 26, 1953 `2,737,386 Reher Mar. 6, 1'95-6 FOREIGN PATENTS 483,077 VGermany ,Sept 25,4 1929 t 916,707 Germ-any Aug. 16, 1954 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No, 3,100,069 August 6, 1963 Howard R. Richards et al.

It is hereby certified that error appears n the above numbered patent requiring correction and that the said Letters Patent should read as corrected below Column 5, line 59, after "and" insert said column 7, line 44, for "for" read from Signed and sealed this 28th day of January 1964.

(SEAL) Attest: EDWIN L. REYNOLDS ERNEST W. SWIDER Attesting Officer AC tim] Commissioner of Patents 

3. WEB GUIDING APPARATUS COMPRISING FIRST AND SECOND ROLL MEANS FOR GUIDINGLY ENGAGING A WEB TRAVELING ALONG A GIVEN DIRECTION AND EXTENDING UNDER ONE OF SAID FIRST AND SECOND ROLL MEANS AND OVER THE OTHER WHEREBY THE DEGREE OF INTERFERENCE BETWEEN THE WEB ENGAGING PROFILES OF SAID FIRST AND SECOND ROLL MEANS AS VIEWED ALONG SAID DIRECTION OF WEB TRAVEL DETERMINES THE DEGREE OF WRAP OF SAID WEB THEREON, ROLL MOUNTING MEANS TO PROGRESSIVELY ADJUST THE PROFILE RELATIONSHIP OF SAID FIRST AND SECOND ROLL MEANS RELATIVE TO EACH OTHER BACK AND FORTH BETWEEN A FIRST CONDITION WHERE, AS BETWEEN SAID FIRST AND SECOND ROLL MEANS, THERE ARE RELATIVELY LOW DEGREES OF (1) SKEWING AND (2) PROFILE INTERFERENCE AND A SECOND CONDITION WHERE, AS BETWEEN SAID FIRST AND SECOND ROLL MEANS, THERE ARE RELATIVELY HIGH DEGREES OF (1) SKEWING AND (2) PROFILE INTERFERENCE, SAID ROLL MOUNTING MEANS INCLUDING MEANS TO SHIFT SAID FIRST AND SECOND ROLL MEANS BACK AND FORTH TOGETHER TRANSVERSE TO THE DIRECTION OF WEB TRAVEL INCIDENT TO SAID PROGRESSIVE ADJUSTMENT BACK AND FORTH BETWEEN SAID FIRST AND SECOND CONDITIONS. 